This invention relates to a connector for a circuit board and more particularly to a connector for a circuit board used in electrical meters, for example, revenue meters of the type used by energy suppliers to accurately measure electrical energy delivered to customers for the purposes of billing and/or collecting revenue, and power quality meters having power quality monitoring, detection, quantification and reporting capabilities.
In a typical electrical distribution system, electrical energy is generated by an electrical supplier or utility company and distributed to customers via a power distribution network. The power distribution network is the network of electrical distribution wires which link the electrical supplier to its customers. Typically, electricity from a utility is fed from a primary substation over a distribution cable to several local substations. At the substations, the supply is transformed by distribution transformers from a relatively high voltage on the distributor cable to a lower voltage at which it is supplied to the end customer. From the substations, the power is provided to industrial users over a distributed power network that supplies power to various loads. Such loads may include, for example, various power machines.
At the customer's facility, there will typically be an electrical energy meter ("revenue meter") connected between the customer and the power distribution network so as to measure the customer's electrical demand. The revenue meter is an electrical energy measurement device, which accurately measures the amount of electrical energy flowing to the customer from the supplier or from the customer to the supplier. The amount of electrical energy measured by the meter is then used to determine the amount for which the energy supplier should be compensated. Typically, revenue meters are socket-based meters. That is, revenue meters will generally be of an A-base or S-base meter, as described in more detail below. Alternatively, revenue meters may also be of the switchboard type, as described in more detail below.
The ANSI standards define two general types of revenue meters, socket based ("S-base" or "Type S") and bottom connected ("A-base" or "Type A"). These types of revenue meters are distinguished by the method by which they are connected to the electric circuit that they are monitoring. This invention pertains to S-base meters. S-base meters feature electrically-conducting bayonets (blade type terminals) disposed on back side of the meter. These electrically-conducting bayonets are designed to align with matching jaws of a detachable meter mounting device such as a revenue meter socket. The socket is hard wired to the electrical circuit and is intended to be installed in a permanent manner. To install an S-base meter, the utility need only plug in the meter into the socket. This makes installation of new meters and especially replacement of defective meters extremely simple. Once installed, the installer need only secure the sealing means, which ensure that the meter will not be tampered with (as detailed in the ANSI standards). To remove the meter, the installer need only pull it out of the socket.
The relevant ANSI standards specify the exact physical and electrical requirements of the blade terminals for the S-base meter. Further, these standards also specify requirements common to both types of meters. These include durability and operating lifetime requirements. They further include requirements for physically sealing the meters. Revenue meters must provide sealing mechanisms to both protect the meter from environmental conditions existing in the installed location as well as protect the meter from unauthorized tampering. Typically, revenue meters are contained entirely within a housing which features a meter cover usually made of a transparent material. Typically, this includes the meter electronics, voltage transformer (PT), current transformer (CT), meter display and user interface as specified by the ANSI standards. It should be noted however, that in certain high voltage applications, other CT and PT's can be located remote from the revenue meter and connected with the meter's internal CT and PT's via the S-base or A-base connection in order to isolate dangerous high voltage signals from the meter. For a more detailed description of revenue meters, the reader is referred to the co-pending applications referred to in the first paragraph of this disclosure, which are all incorporated herein by reference.
The present invention simplifies the assembly of the connector between the bayonets or blades and the circuit board. That is, prior to this invention, electrically conducting bayonets were traditionally held in place by cotter pins. A wire harness which was soldered to each individual bayonet was used to connect the bayonets to the measuring circuitry of the meter. Inserting the cotter pins and soldering the wiring harness to the individual bayonets is time consuming since it introduces additional manufacturing steps.
Therefore, it is an object of the present invention to simplify the manufacturing process for attaching bayonets to an S-type revenue meter base by soldering the bayonets directly into a printed circuit board, mounting the printed circuit board on the base, thereby eliminating the need for cotter pins and a wiring harness.